1. Field of the Invention
The present invention relates to marine vessels for use in retrieving oil that has been spilled into an aquatic marine environment, and more particularly relates to an improved oil recovery system for use in a marine environment wherein a deep draft vessel provides an oil holding interior that includes one or more oil separators positioned under the water surface of the vessel interiors so that oil separation takes place underwater, enhancing oil/water separation and providing for continuous and/or intermittent discharge of water and continuous and/or intermittent batch-type removal of the separated oil. Further, an improved influent flow conduit system enhances accumulation of oil at multiple stages as an oil/water mixture is gathered from the surrounding marine environment.
2. General Background
In the clean-up of oil spills, it has been known to use vessels having an intake that skims a combination of oil and water into the vessel interior. Thereafter, the oil is separated by pumping it into separators or by simply filling the vessel completely to its capacity with whatever oil can be skimmed. The problem with such vessels is that they are limited by the capacity of their interior oil containing compartment which can be only a very small fraction of the overall volume of oil contained in the spill.
Another problem with oil skimmer vessels is that they must typically be large enough to contain a sufficient volume of oil so that their construction is very expensive as compared to their ability to contain a certain volume of oil.
Other types of skimmers include an elongated endless belt in the form of a brush-type structure which is dispensed to the oil slick and which returns to a mother ship where a squeezing mechanism separates the oil which accumulates in the endless belt.
Other types of oil skimmers include long flexible booms that accumulate the oil in to a central area within the boom so that pumps can simply suction the accumulated oil into a container such as a barge. The problem with booms is that so often the oil spreads quickly and cannot be boomed off before it has spread over an area much larger than the boom itself can encompass.
Another problem with prior art-type oil skimmer devices is that they are usually large, clumsy, and have an inability to quickly be placed in service at the time the spill occurs.
Thus, there is a need for a relatively small, yet efficient oil retrieving vessel which not only accumulates oil but also continuously separates the oil from the collected water so that it can be quickly and continuously dispensed to a remote collection facility such as a barge.
It is thus an object of the present invention to provide an improved oil/water separation system that functions in a marine environment to continuously ingest large volumes of floating oil and the adjacent seawater for internal separation.
It is further object of the present invention to provide an improved marine vessel oil skimmer that can handle large volumes of an oil/seawater mixture with relatively small vessel size.
It is another object of the present invention to provide an improved oil/water skimmer in the form of a marine vessel that separates oil and water at multiple locations along an influent conduit path.